The invention relates to a telemetry monitoring system and a data recovery method for a telemetry monitoring system.
Firefighters and other rescue personnel are often required to enter hazardous environments, such as burning buildings. In such circumstances, the firefighter is provided with self-contained breathing apparatus (SCBA) which provides breathable gas to the firefighter.
Breathing apparatus may be provided with an electronic monitoring unit which provides information to the firefighter. This information may include the amount of breathable gas remaining, cylinder pressure, time-to-whistle (TTW), and temperature, for example. This information can be monitored by the firefighter to allow them to work safely and within the restrictions of the breathing apparatus. The monitoring unit may also perform the functions of an automatic distress signal unit (ADSU), otherwise referred to as a personal alert safety system (PASS). Such devices are provided with a motion sensor, a panic button, and an alarm. If the device does not detect motion within a pre-determined period of time then an audible pre-alarm is activated. If this pre-alarm is not cancelled by either movement or by pressing a button within a pre-determined period of time then an audible full-alarm is activated. This indicates to others in the vicinity that the wearer is in distress. The panic button can also be manually activated to sound the alarm if required. British Home Office Standard JCDD/38 specifies the requirements of an ADSU.
To ensure the safety of a firefighter within a hazardous environment, it is also desirable to monitor their status from outside of the incident. This is typically the responsibility of a designated entry control officer.
Typically, the entry control officer uses an entry control board (ECB) to record information regarding the firefighters. Each firefighter who enters the incident wearing breathing apparatus is recorded on the ECB. This may be achieved by removing an identification tag (or tally) from their breathing apparatus and slotting the tag into the board. The time the firefighter entered the incident is written next to their identification tag and their “time to whistle” is manually calculated based on the capacity of their cylinder of breathable gas.
More recently, electronic entry control boards have been implemented. Such electronic boards are able to remotely monitor the breathing apparatus of the firefighter from outside of the incident. Each firefighter is provided with a radio unit, which is connected to the electronic monitoring unit and which transmits telemetry data to the ECB. The telemetry data includes data such as the amount of breathable gas remaining, cylinder pressure, time-to-whistle (TTW), and temperature. Accordingly, the information displayed on the entry control board is “live” data and is not based on calculations made at the time of entry. The telemetry data may also include any pre-alarms or full-alarms initiated by the ADSU/PASS. Also, the entry control officer may relay information to the firefighter using the entry control board. For example, the entry control officer may transmit an evacuation signal to the firefighter which informs the firefighter to exit the incident.
While such telemetry monitoring systems provide far superior monitoring of firefighters, they are susceptible to hardware and software failures. Such failures prevent the entry control officer from being able to monitor the firefighters from outside of the incident. Consequently, the firefighter is then solely responsible for monitoring the status of their breathing apparatus. For that reason, telemetry monitoring systems are usually regarded as an additional safety feature and are not intended to replace any other safety feature or procedure.
The possible failure of the telemetry monitoring system is generally seen as an acceptable risk. Nevertheless, it is desirable to be able to quickly and reliably recover the telemetry monitoring system in the event of a failure so as to continue monitoring the firefighters.